WAUSAU — Fire crews battled bitterly cold temperatures as they brought an early morning fire under control at an east side duplex in Wausau.

The blaze broke out at around 12:30 a.m. in the 500 block of Chicago Avenue, according to the Wausau Police Department. By the time crews arrived, residents from both units inside the duplex, along with their pets, had safely escaped.

No one was injured.

The cause of the blaze has not yet been determined.